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Related papers: Universal Guard Problems

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We consider methods for finding a simple polygon of minimum (Min-Area) or maximum (Max-Area) possible area for a given set of points in the plane. Both problems are known to be NP-hard; at the center of the recent CG Challenge, practical…

Computational Geometry · Computer Science 2021-11-11 Sándor P. Fekete , Andreas Haas , Phillip Keldenich , Michael Perk , Arne Schmidt

We prove that there is a universal measure on the unit circle such that any probability measure on the unit disk is the limit distribution of some subsequence of the corresponding orthogonal polynomials. This follows from an extension of a…

Spectral Theory · Mathematics 2007-05-23 Barry Simon , Vilmos Totik

The Yang-Baxter equation and it's various forms have applications in many fields, including statistical mechanics, knot theory, and quantum information. Unitary solutions of the braided Yang-Baxter equation are of particular interest as…

Quantum Physics · Physics 2023-04-04 David Lovitz

In [1] the problem of finding a sharp lower bound on lower against number of a general graph is mentioned as an open question. We solve the problem by establishing a tight lower bound on lower against number of a general graph in terms of…

Combinatorics · Mathematics 2019-08-27 Babak Samadi

This paper initiates the study of quantum algorithms for matroid property problems. It is shown that quadratic quantum speedup is possible for the calculation problem of finding the girth or the number of circuits (bases, flats,…

Quantum Physics · Physics 2022-03-28 Xiaowei Huang , Jingquan Luo , Lvzhou Li

A set P of points in R^2 is n-universal, if every planar graph on n vertices admits a plane straight-line embedding on P. Answering a question by Kobourov, we show that there is no n-universal point set of size n, for any n>=15. Conversely,…

Computational Geometry · Computer Science 2013-08-28 Jean Cardinal , Michael Hoffmann , Vincent Kusters

The Art Gallery Problem (AGP) asks for placing a minimum number of stationary guards in a polygonal region P, such that all points in P are guarded. The problem is known to be NP-hard, and its inherent continuous structure (with both the…

Computational Geometry · Computer Science 2014-12-19 Sándor P. Fekete , Stephan Friedrichs , Alexander Kröller , Christiane Schmidt

In this paper we prove that the uniform one-dimensional guarded fragment, which is a natural polyadic generalization of the guarded two-variable logic, has the Craig interpolation property. We will also prove that the satisfiability problem…

Logic in Computer Science · Computer Science 2021-10-15 Reijo Jaakkola

We introduce the theory of div point sets, which aims to provide a framework to study the combinatoric nature of any set of points in general position on an Euclidean plane. We then show that proving the unsatisfiability of some first-order…

Combinatorics · Mathematics 2019-09-02 Archy Will He

We provide upper bounds for the cardinality of the value set of a polynomial map in several variables over a finite field. These bounds generalize earlier bounds for univariate polynomials.

Number Theory · Mathematics 2012-10-31 Gary L. Mullen , Daqing Wan , Qiang Wang

We provide lower and upper bounds on the minimum size of a maximum stable set over graphs of flag spheres, as a function of the dimension of the sphere and the number of vertices. Further, we use stable sets to obtain an improved Lower…

Combinatorics · Mathematics 2022-04-05 Maria Chudnovsky , Eran Nevo

In this note we analyze two algorithms, one for producing a matching and one for an independent set, on $k$-uniform $d$-regular hypergraphs of large girth. As a result we obtain new lower bounds on the size of a maximum matching or…

Combinatorics · Mathematics 2023-07-31 Deepak Bal , Patrick Bennett

In this extended abstract, we present a PTAS for guarding the vertices of a weakly-visible polygon $P$ from a subset of its vertices, or in other words, a PTAS for computing a minimum dominating set of the visibility graph of the vertices…

Computational Geometry · Computer Science 2018-10-02 Matthew J. Katz

We show that there are sets of $n$ points in the plane with $n$ arbitrarily large that contain more than $n^{1.014}$ pairs of points separated by a distance exactly $1$. This improves on very recent work of a team at OpenAI, who proved the…

Combinatorics · Mathematics 2026-05-21 Will Sawin

Given a closed simple polygon $P$, we say two points $p,q$ see each other if the segment $pq$ is fully contained in $P$. The art gallery problem seeks a minimum size set $G\subset P$ of guards that sees $P$ completely. The only currently…

Computational Geometry · Computer Science 2024-08-07 Simon Hengeveld , Tillmann Miltzow

We prove a quantum query lower bound \Omega(n^{(d+1)/(d+2)}) for the problem of deciding whether an input string of size n contains a k-tuple which belongs to a fixed orthogonal array on k factors of strength d<=k-1 and index 1, provided…

Quantum Physics · Physics 2013-04-04 Robert Spalek

The chosen tool of this thesis is an extremal type approach. The lesson drawn by the theorems proved in the thesis is that surprisingly small compromise is necessary on the efficacy of the solutions to make the approach work. The problems…

Combinatorics · Mathematics 2017-11-09 Tamás Róbert Mezei

Given a finite grid in $\mathbb{R}^2$, how many lines are needed to cover all but one point at least $k$ times? Problems of this nature have been studied for decades, with a general lower bound having been established by Ball and Serra. We…

Combinatorics · Mathematics 2023-05-02 Anurag Bishnoi , Simona Boyadzhiyska , Shagnik Das , Yvonne den Bakker

We solve the problem of finding a sharp upper bound on the minimum angle formed by $N$ points in the Euclidean and Hyperbolic planes.

General Mathematics · Mathematics 2007-05-23 Ghislain Jaudon , Hugo Parlier

We study the problem of planning paths for a team of robots for visually monitoring an environment. Our work is motivated by surveillance and persistent monitoring applications. We are given a set of target points in a polygonal environment…

Robotics · Computer Science 2016-12-13 Pratap Tokekar , Ashish Kumar Budhiraja , Vijay Kumar